Wide angle lens

I'm looking into a Canon wide angle lens I want to use mainly for landscape photos in the f11 - f22 range. I'm thinking of the 35mm f1.4 and 20 mm f2.8 OR 16-35 f2.8 or will the 17-40 f4 be just as good for what I need? Thank you.

I don't know what camera you are using but keep in mind that on most digital SLR cameras (the ones with APS size sensors) a 20mm lens is not that wide for landscape photography. On such a camera the 16-35mm would be a better bet.

On 35mm film or full frame digital (5D, 1Ds)...16mm, 17mm or 20mm would be really wide.
On APS-C sensor digital cameras (10D, 20D, 30D, Rebels)...you will need something like the Canon EF-S 10-20mm, to get really wide views.

I would probably choose the 20mm f2.8
It´s got all the drama you´ll need, and anyway, who does landscapes wide open? You´re best off stopping down to around f8 for overall sharpness, and depth of field.

The 35mm f1.4 is indeed a nice lens, but more suited to classic street and hand-held photography.